<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Vue中的动画封装</title>
    <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
    <style>
        .v-enter, .v-leave-to {
            opacity: 0;
        }
        .v-enter-active, .v-leave-active {
            transition: opacity 1s;
        }
    </style>
</head>
<body>
    <div id="app">
        <!-- <transition>
            <div v-show="show">hello world</div>
        </transition> -->
        <fade :show="show">
            <div>hello world</div>
        </fade>

        <fade :show="show">
            <h1>死亡我晨儿</div>
        </fade>
        <button @click="handleBtnClick">toggle</button>
    </div>

    <script>
        Vue.component('fade', {
            props: ['show'],
            template: `
                <transition @before-enter="handleBeforeEnter" @enter=""handleEnter>
                    <slot v-if="show"></slot>
                </transition>
            `,
            methods: {
                handleBeforeEnter: function(el) {
                    el.style.color = 'red';
                },
                handleEnter: function(el, done) {
                    setTimeout(() => {
                        el.style.color = 'green';
                        done();
                    }, 2000)
                }
            }
        })

        var vm = new Vue({
            el: '#app',
            data: {
                show: true
            },
            methods: {
                handleBtnClick: function() {
                    this.show = !this.show;
                }
            }

        })
    </script>
</body>
</html>